Two spheres A and B of radius ‘a’ and ‘b’ respectively are at same electric potential. The ratio of the surface charge densities of A and B is

Given electric potential of spheres are same i.e. VA=VB⇒14πε0⋅Q1a=14πε0⋅Q2b⇒Q1Q2=ab          …(i)as surface charge density σ=Q4πr2⇒σ1σ2=Q1Q2×b2a2=ab×b2a2=ba